Test of Lorentz Invariance at the South Pole

洛伦兹对称性是自然界的一种特征，它使实验结果与实验室在空间中的取向或提升速度无关，它是量子场论和广义相对论的基础。它们的统一被认为是物理学中最大但尚未得到满足的挑战之一。狭义相对论假定所有物理定律在洛伦兹变换下都是不变的，洛伦兹变换包括普通的旋转和参照系的速度变化。随后，量子场论都在其基本结构中融入了洛伦兹不变性。与其他基本力不同，重力的特征是一个维度耦合常数，它引入了普朗克标度的特征能量。然而，这种固定的高能标度的存在并不是洛伦兹不变的；因此，洛伦兹对称性测试作为探索量子引力实验效应的最有前途的方法之一引起了人们的极大兴趣。发展了各自的高灵敏度实验技术，以寻找由洛伦兹破坏自旋相互作用引起的空间各向异性。地球实验室的空间各向异性主要由三个效应定义：重力、磁场和地球自转。自旋测量对模拟洛伦兹破坏效应的旋转特别敏感，而重力会影响仪器的机械稳定性。相比之下，磁场可以相对容易地被屏蔽。因此，这种实验最各向同性的位置是在地球自转向量与重力向量平行的地理极点之一。该奖项旨在通过在南极南极站部署一个非常灵敏的原子自旋传感器，以前所未有的精度测试洛伦茨不变性，在那里它不受地球自转的影响。这项实验将把几种可能的洛伦兹破坏形式限制在可以预期量子引力效应的敏感范围内，将现有的限制提高数千倍。该项目将作为对宇宙空间各向同性的简单测试而引起广泛关注，对任何有限效应的观察肯定会对理解时空在物理学中最具挑战性的问题之一产生巨大影响？重力的起源。该项目还将涉及对博士后和研究生和本科生的培训。

Lorentz symmetry, the feature of nature that makes experimental results independent of the orientation or the boost velocity of the laboratory through space, lies at the foundation of both the quantum field theory and the theory of general relativity. Their unification is regarded as one of the biggest, but yet unmet, challenges in physics. Special relativity postulates that all laws of physics are invariant under Lorentz transformations, which include ordinary rotations and changes in the velocity of a reference frame. Subsequently, quantum field theories all incorporated Lorentz Invariance in their basic structure. The force of gravity, unlike other fundamental forces, is characterized by a dimensionful coupling constant that introduces a characteristic energy of the Plank scale. However, the existence of such fixed high energy scale is not Lorentz-invariant; hence, tests of Lorentz symmetry attract a lot of interest as one of the most promising ways for searching experimental effects of the quantum gravity. Respective high-sensitivity experimental techniques were developed to search for a spatial anisotropy caused by Lorentz-violating spin interaction. Spatial anisotropy of an Earth laboratory is mainly defined by three effects: gravity, magnetic fields, and Earth rotation. Spin measurements are particularly sensitive to rotations which mimic Lorentz violating effects, while gravity affects the mechanical stability of the apparatus. In contrast, magnetic fields can be relatively easily shielded. Therefore, the most isotropic location for such experiments is at one of the geographic poles, where Earth rotation vector is parallel to the gravity vector. This award is to test Lorentz Invariance with unprecedented precision by deploying a very sensitive atomic spin sensor at the South Pole Station in Antarctica, where it is unaffected by the Earth's rotation. The experiment will constrain several possible forms of Lorentz violation in the sensitivity range where the effects of quantum gravity can be expected, improving existing limits by a factor of thousand. The project will attract wide attention as a simple test of the spatial isotropy of the Universe, and observation of any finite effects would certainly have a tremendous impact on the understanding of space-time shedding light on one of the most challenging problems in physics ? origin of gravity. The project will also involve training for the postdocs and students at the graduate and undergraduate levels.